Kidney Function Test (KFT): Understanding Your Report

By Dashvanth Healthcare Medical Team · Reviewed by our specialists · East Delhi

Why Kidney Function Tests Matter

The kidneys filter 200 litres of blood daily, removing waste and maintaining electrolyte balance. Chronic Kidney Disease (CKD) affects ~17% of India's adult population — mostly silently until advanced. Regular KFTs enable early detection when treatment is most effective.

Key KFT Components

Serum Creatinine

• Muscle waste product filtered by kidneys
• Normal: Men 0.7–1.3 mg/dL; Women 0.6–1.1 mg/dL
• Rises when GFR falls below 50% — not sensitive for early CKD
• High protein diet, large muscle mass, and dehydration can elevate creatinine without kidney disease

eGFR (Estimated Glomerular Filtration Rate) — MOST IMPORTANT

• Calculated from creatinine, age, and sex (CKD-EPI formula)
• Normal: >90 mL/min/1.73m²
• CKD staging: G1 (>90, with markers), G2 (60–89), G3a (45–59), G3b (30–44), G4 (15–29), G5 (<15 = kidney failure)
• Requires kidney specialist referral when eGFR <45

Blood Urea / BUN

• Normal: 7–20 mg/dL (BUN); Urea 15–45 mg/dL
• High: kidney disease, high protein diet, dehydration, GI bleeding
• Low: liver disease, malnutrition

Uric Acid

• Normal: Men 3.5–7.2 mg/dL; Women 2.6–6.0 mg/dL
• High (hyperuricaemia): gout, kidney disease, metabolic syndrome

Electrolytes (Sodium, Potassium)

• Abnormal electrolytes: often first sign of significant kidney dysfunction
• Hyperkalaemia (high potassium) in CKD = cardiac risk — requires urgent management